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One major obstacle to understanding the mechanisms behind the acquisition and expression of habits seems to be the conceptual confusion that has reigned in this area of psychology research for so many decades. This confusion (or lack of consensus) is largely due to the fact that, between the 1960s and early 1990s, research on this topic was conducted in parallel in the fields of animal and human cognitive science, leading to terminological differences. Understanding how the concept of habit emerged makes it possible to identify and define the various related terms or synonyms, to know how they came about, and, ultimately, to propose an operational and consensual definition of habits.This article provides a brief history of the concept of habit in the humanities, psychology, and cognitive neuropsychology. It is divided into six parts. First, we relate the earliest occurrences of the term at the end of the nineteenth century, in the field of human sciences. Second, we look at the behavioral context in which the concept of habit was originally studied in psychology. Third, we describe how cognitive psychologists abandoned this concept in order to develop related but distinct concepts. Fourth, we examine how cognitive neuropsychology studies in patients with amnesic syndromes led to habit being conceptualized as a subcomponent of nondeclarative memory. Fifth, we discuss the reemergence of parallel studies in animals and humans, especially studies of frontal-subcortical syndromes. Sixth, and finally, we identify areas of apparent agreement, as well as those subject to debate (or at least discussion), in this promising research on the neuropsychology of habit.